Fri, 09 Jun 2006
10:00
DH 3rd floor SR
Thu, 08 Jun 2006
16:30
DH 1st floor SR

A teleparallel reformulation of Dirac's equation or quantum electrodynamics for dummies

Dimitri Vassiliev
(University of Bath)
Abstract
The price we pay for this simplicity is that the change of variable
spinor --> coframe
makes the Dirac equation nonlinear. The morale of the talk is that, in our opinion, it is more natural to view the Dirac equation as a nonlinear equation for the unknown coframe rather than a linear equation for the unknown spinor.
Thu, 08 Jun 2006

14:00 - 15:00
Comlab

Modelling cerebrospinal fluid flow through the brain and hydrocephalus

Dr Ian Sobey
(University of Oxford)
Abstract

An integral part of the brain is a fluid flow system that is separate from brain tissue and the cerebral blood flow system: cerebrospinal fluid (CSF) is produced near the centre of the brain, flows out and around the brain, including around the spinal cord and is absorbed primarily in a region between the brain tissue and the skull. Hydrocephalus covers a broad range of anomalous flow and pressure situations: the normal flow path can become blocked, other problems can occur which result in abnormal tissue deformation or pressure changes. This talk will describe work that treats brain tissue as a poroelastic matrix through which the CSF can move when normal flow paths are blocked, producing tissue deformation and pressure changes. We have a number of models, the simplest treating the brain and CSF flow as having spherial symmetry ranging to more complex, fully three-dimensional computations. As well as considering acute hydrocephalus, we touch on normal pressure hydrocephalus, idiopathic intracranial hypertension and simulation of an infusion test. The numerical methods used are a combination of finite difference and finite element techniques applied to an interesting set of hydro-elastic equations.